Typically an access floor includes a metallic frame and tiles placed on the metallic frame. In the case of a seismic event, the tiles can overlap each other, drop down from the frame, and/or be distorted.
FIG. 1 shows a top view of a plurality of flooring elements, each indicated at 10, arranged in an array 12 during normal use. FIG. 2 shows how lateral loads A, B due to seismic activity can cause the flooring elements 10 to shift with respect to each other, so they are no longer aligned in the array 12. FIG. 3 shows how a primarily horizontal load C and a primarily vertical load D, both caused by seismic activity, can cause one flooring element 10A to overlap an adjacent flooring element 10B.
EP 2322739 discloses a support for raised flooring elements. A connection element is provided between a bottom face of a flooring element and a bearing surface of a top end of a support said connection element. A first coupling means is designed to fit into corresponding seats formed in the bottom face of the flooring element.
However, the structure of EP 2322739 does not retain the flooring element on the support under seismic loads.